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The topology of a polymer is normally a fixed property of the material, derived from the characteristic of the monomers and their linkages. Here the authors present a method to transform the topology of block copolymers containing rotaxane linkages via acetylation.

A nitrile N-oxide-functionalized polypeptide was synthesized by a two-step method involving the combination of ring-opening polymerization of an amino acid N-carboxyanhydride (NCA) monomer using a primary amine initiator containing a nitroalkane group and a subsequent terminal conversion. The formed peptide was fully characterized by NMR, FT-IR, and MALDI-TOF MS measurements. The catalyst-free grafting reaction of the formed functionalized peptide with rubbers containing double bonds was achieved with high efficiency via an environmentally benign process. These results surely contributed to the development of novel peptide-grafted polymers.

Optically active polymers and supramolecules that form well-defined architectures are important materials with a wide range of applications. Amino acids and sugars are great candidates for the preparation of optically active functional materials because of their versatile structures and functional groups. In these chiral units, intra- and intermolecular noncovalent interactions play significant roles in the generation of smart functions. In this focus review, the author reviews his recent studies related to the fabrication and functions of chiral conjugated polymers and chiral supramolecules based on these natural chiral compounds.

A dinuclear Pd(II) complex possessing a cyclic ligand was applied as a coordinative cross-linker of acrylonitrile–butadiene rubber (NBR). Tensile tests revealed that the mechanical properties of the coordinatively cross-linked NBRs were improved compared with those of the original NBR. Increasing the loading amount of the complex enhanced Young’s modulus, tensile strength, tensile strain, and toughness. The cross-linked NBR could be reused with a simple dissolution and drying process, which featured coordinative cross-linking.

We synthesized novel benzoxazine-polymers, poly(1)_230–2000 consisting of rigid phenyleneethynylene and flexible polypropylene glycol (PPG) moieties in the main chain. Resins obtained by cross-linking reaction of poly(1)_230–2000 were thermally as stable as a previously synthesized polybenzoxazine resin containing phenyleneethynylene moieties. Introduction of flexible PPG unit was effective to lower the curing temperature, and enhance mechanical toughness keeping thermal stability.

Solvent-free base-catalyzed CO₂ fixation into polymers having 2-pyridyl group-substituted propargylamine moieties in the main and side chains was achieved under atmospheric CO₂ condition. The reactivity of the polymer films was improved by the introduction of pendant tertiary amine moiety.

An effective method for the synthesis of the rotaxane cross-linked polymers (RCPs) was developed using a metal-containing supramolecular cross-linker (MSC). Radical polymerization of several vinyl monomers and bulky end-capped comonomer afforded RCPs in high yields. The obtained RCPs exhibited thermal properties corresponding to their respective polymer skeletons. Swelling ratio gradually increased with the decreasing amount of the steric comonomer units, indicating that the sliding ability of the movable cross-linker is strongly related to the swelling ability.

Acquired uniparental disomy (aUPD), a common feature of cancer genomes, is associated with gain-of-function mutations of proto-oncogenes as well as with loss-of-function mutations of tumour suppressor genes. Here, gain-of-function mutations of the C-CBL tumour suppressor are shown to be tightly associated with aUPD of the 11q arm in certain myeloid neoplasms.

The cohesin complex mediates sister chromatid cohesion during cell division. Now, Seishi Ogawa and colleagues report largely mutually exclusive mutations in multiple members of the cohesin complex in acute myeloid leukemia, myelodysplastic syndromes, chronic myelomonocytic leukemia, chronic myelogenous leukemia and classical myeloproliferative neoplasms.

Catechol-modified alginates (AlgDAs) with various catechol contents were synthesized and examined as adhesive materials. AlgDA exhibited high adhesive strength with mica and moderate adhesive strength with polymer resins, although this adhesiveness was not observed for sodium alginate. AlgDA with a relatively low catechol content exhibited relatively high adhesive strength, unlike other catechol-modified polymer adhesives. AlgDA residues were successfully removed from the used substrates by a simple water washing process. AlgDA is promising as a biobased adhesive material that contributes to a sustainable society.

Hydroxy-tethered platinum(II) complexes were synthesized and used as diol monomers for polyurethane synthesis. Polyurethanes with moderate molecular weights were obtained by conventional polyaddition with a diisocyanate. The polyurethane containing the platinum(II) complex substituted with t-Bu groups was soluble in common organic solvents, including CHCl₃ and tetrahydrofuran. The obtained polyurethane exhibited distinguishable photoluminescence changes upon grinding in the solid state.